LlamaIndex or Haystack
Choose these when data connectors, retrieval pipelines, and document workflows matter more than general chaining.
Framework comparison
LangChain is useful for many AI apps, but it is not the only path. Builders often need a RAG-first framework, a stateful agent runtime, a model gateway, a prompt optimization tool, or a smaller custom stack.
Last updated May 21, 2026. Framework APIs change quickly; check official docs before committing a production architecture.
Quick picks
Choose these when data connectors, retrieval pipelines, and document workflows matter more than general chaining.
Use graph/state concepts when agents need retries, approvals, memory, branching, or human review.
Useful when your app already lives near .NET, Azure, enterprise workflows, or planner-style orchestration.
For a small production workflow, direct SDK calls plus your own logging, queues, and evals may be easier to maintain.
| Framework path | Best for | Why choose it | Watch out for |
|---|---|---|---|
| LlamaIndex | RAG and data-to-LLM apps | Strong data ingestion and retrieval-oriented concepts | Still needs evaluation, deployment, and observability decisions |
| Haystack | Search and document QA pipelines | Pipeline mental model works well for retrieval systems | May be more framework than a tiny demo needs |
| Semantic Kernel | Enterprise and Microsoft-aligned apps | Planner and skill patterns can fit larger software teams | Best when your stack matches its ecosystem |
| LangGraph-style orchestration | Stateful agents and approval workflows | Explicit state, nodes, and transitions help production agents | Requires careful state and error design |
| DSPy | Prompt/program optimization experiments | Useful when you want measurable prompt and retrieval optimization | Different mental model from typical app frameworks |
| LiteLLM or model gateway | Provider routing and fallback | One interface for multiple LLM providers | Does not replace app logic, evals, or data pipelines |
| Custom small stack | Simple production workflows | Fewer dependencies and clearer ownership | You must build retries, logging, evals, and guardrails yourself |
Decision method
If wrong retrieval is the main risk, choose a RAG-oriented framework and invest in evals. If runaway tool calls are the risk, choose a stateful agent runtime. If provider lock-in is the risk, use a model gateway. If complexity is the risk, build the smallest custom workflow.
People also ask
Sometimes. If the project is one prompt and one API call, a direct SDK may be cleaner. Use a framework when it helps with retrieval, tools, state, routing, or evaluation.
LlamaIndex and Haystack are common RAG-oriented choices. The better choice depends on your data sources, evaluation needs, deployment style, and team familiarity.
Yes, especially for simple workflows. But once you need branching state, retries, approvals, audit logs, and durable tool calls, a stateful agent framework can reduce risk.